Cardboard blank



The sole FIGURE is a plan view of a cardboard blank showing our new design.

The broken lines in the sole FIGURE depict portions of the cardboard blank that form no part of the claimed design. Solid lines located on internal edges of the cardboard blank in the sole FIGURE and having a lighter line weight than the solid lines located on perimeter edges represent panel crease lines. Solid lines located on internal edges of the carton blank in the sole FIGURE and having the same line weight as the solid lines located on perimeter edges represent cuts or partial cuts in the cardboard blank. 

CLAIM The ornamental design for a portion of cardboard blank, as shown and described. 